The present invention relates to a disk recording/reproducing apparatus for recording/reproducing information onto/from an optical disk and a test writing method in such the apparatus, and in particular, it relates to a method for determining a test writing area during the recording process thereof.
An optical disk, being a disc-like optical information recording medium, is widely used, as a medium for enabling accessing to data at high-speed, but without contact thereon, and having a large memory capacity and a low cost thereof, for example, for use of recording/reproducing of audio digital data and digital video data, and further as an external memory device of a computer. On such the optical disk are provided regions or areas, being so-called “test writing area” (PCA), putting so-called a program area, which is usable for a user, between them, i.e., an inner periphery and an outer periphery thereof.
In this manner, because the test writing areas are located on the inner/outer peripheries of the disk, in normal, test writing is executed, basically, on both sides, i.e., the inner/outer peripheries of the disk, when staring the apparatus, etc., for adjusting a power of a laser beam, appropriately, within the optical disk recording apparatus. On the other hand, the test writing mentioned above is also executed, when an error occurs during the recording process, because of reasons of inappropriateness or improperness of power of the laser beam or the like, within the optical disk recording apparatus. However, in such the cases, as was mentioned above, because the test writing areas are provided on both the inner/outer peripheries of the disk, basically, the test writing is executed on both of the inner/outer peripheries; however, the test writing to be executed during the recording process of the apparatus is done, in many cases, only upon one side of the areas, i.e., those provided on the inner periphery or the outer periphery, due to the reasons of time-out (i.e., lowering of transfer rate due to the fact that the process is not executed within a preset time-period, which is determined by OS, etc.) and so on.
For example, in the following Patent Document 1 is already known a recording apparatus and a method for recording data with the most suitable recording power, by conducting the test writing on a selected one, being near from the recording position of data, between those PCAs, which are provided on both the inner periphery and the outer periphery of the program area.
Also, in the following Patent Document 2 is already known an apparatus for conducting the test writing upon any one or on both of the test wiring areas provided on the inner periphery and the outer periphery of the disk, when executing it, i.e., for the purpose of conducting the recording at the most suitable laser power, by taking non-uniformity of physical properties into the consideration, such as, unevenness of pasting of pigment and/or a curvature of the optical disk, etc., of CD-R, for example.
[Patent Document 1] Japanese Patent Laying-Open No. 2005-209241 (2005); and
[Patent Document 2] Japanese Patent Laying-Open No. 2003-168216 (2003).
Thus, as was mentioned in the above, as the method for determining an area to be executed with the test writing, in relation to the conventional arts, the test writing is conducted on the area on the side near to the recording portion, or determination is made on the area to be executed with the test writing by taking a starting portion and an ending position of the recording. However, the test wiring only on one side of the areas, comparing to the test writing conducted on both of the inner/outer peripheries, lowers down the accuracy when obtaining the most suitable power at the position where data is just recorded from now. Also, the laser power obtained through the test writing is not always suitable, and thereafter it is also necessary to execute it depending on the necessity thereof; for that reason, it is important to determine the area (i.e., the inner periphery side or the outer periphery side) where the test writing should be executed, for the purpose of improving the recording quality while suppressing the rotation number down to the minimum.